Chronic inflammation may result from failure of the host response to engage pro-resolving pathways. The current treatment armamentarium for chronic inflammatory conditions may lead to immune suppression. Thus, identification of novel therapeutics that control inflammation without immune suppression will provide an attractive alternative approach. This is especially important since incidence of these conditions increases with an ageing global population. In planaria, mice, human peripheral blood and milk I recently uncovered a new family of endogenous molecules, named Maresin Conjugates in Tissue Regeneration (MCTR). These potently regulate white blood cell responses, promote the resolution of acute inflammation and accelerate tissue regeneration. The aim of this Starting Grant was to identify pathways that lead to failed resolution in inflammatory arthritis, as a prototypical chronic inflammatory condition. The hypothesis was that MCTR biosynthesis is dysregulated in inflammatory arthritis, leading to an unbridled host response, chronic inflammation and tissue destruction. This proposal was to employ a multipronged approach to test this hypothesis by 1) Determining MCTR regulation in self-resolving and delayed-resolving arthritis; 2) Investigating the host protective and tissue regenerative actions of MCTRs in inflammatory arthritis; 3) Establishing the MCTR biosynthetic pathway and 4) Determining the regulation if its components during self-limited and delayed-resolving arthritis.
The findings made during this grant demonstrate that MCTRs carry potent anti-inflammatory and tissue regenerative activities in experimental joint inflammation reducing both clinical signs of arthritis and promoting the repair or damaged tissues. These findings are significant since we also found that in patients with rheumatoid arthritis (RA) MCTR levels are reduced i with increasing with disease severity. Therefore these results suggest that MCTRs may be useful novel diagnostics and therapeutics in the management and treatment of patients with RA.